# 计算圆的面积
r = 5
PI = 3.14
area = PI * r * r
print("半径{0:3d}圆的面积是{1:10.2f}".format(r, area))
print("半径{0:>3d}圆的面积是{1:>10.2f}".format(r, area))
print("半径{0:^3d}圆的面积是{1:^10.2f}".format(r, area))
print("半径{0:<3d}圆的面积是{1:<10.2f}".format(r, area))
